extensions: Add TI's repo and install specified packages in k3-*

Texas Instruments maintains a custom apt repository [0] that contains:
    * tools like k3conf, which run on K3 devices
    * TI's versions of upstream packages (such as mesa)
    * out-of-tree drivers and firmware for graphics, wifi etc

Therefore, add TI's custom repository as the highest priority repository
in the filesystem. Doing this ensures that if apt finds a version of a
package that exists in both upstream Debian and the TI repository, it
picks the latter.

Additionally, introduce K3_PACKAGES variable to store a list of packages
that should be installed by-default in a K3 image. Initialize it to hold
TI's CC33xx packages.

Also set EXTRAWIFI to "no" in `current` image.

[0] https://github.com/TexasInstruments/ti-debpkgs

Co-authored-by: Suhaas Joshi <s-joshi@ti.com>
Signed-off-by: Suhaas Joshi <s-joshi@ti.com>

config/boards/sk-am62b.conf

@@ -15,3 +15,4 @@ SERIALCON="ttyS2"
 ATF_BOARD="lite"
 OPTEE_ARGS="CFG_TEE_CORE_LOG_LEVEL=1"
 OPTEE_PLATFORM="k3-am62x"
+CC33XX_SUPPORT="yes"

config/sources/families/k3.conf

@@ -20,6 +20,15 @@ declare -g SPD_OPTEED="SPD=opteed"
 
 declare -g INSTALL_HEADERS="yes"
 
+declare -g TI_PACKAGES=()
+if [[ "${CC33XX_SUPPORT}" == "yes" ]] ; then
+	if [[ "${RELEASE}" == "trixie" || "${RELEASE}" == "noble" ]] ; then
+		TI_PACKAGES+=("cc33xx-fw" "cc33xx-target-scripts" "cc33conf" "cc33calibrator")
+	fi
+fi
+
+enable_extension "ti-debpkgs"
+
 case "${BRANCH}" in
 
 	current | current-rt)
@@ -32,6 +41,7 @@ case "${BRANCH}" in
 		declare -g OPTEE_BRANCH="tag:4.6.0"
 		declare -g TI_LINUX_FIRMWARE_BRANCH="${CORESDK_TAG}"
 		declare -g BOOTBRANCH="${CORESDK_TAG}"
+		EXTRAWIFI="no"
 		;;
 
 	edge)